With the introduction of MySQL, in 1995, almost immediately developers started to take advantage of it. Before long however, malicious development ensued that ended up with a vast wasteland of damage.
Hard disks in 1995 were comparatively small in capacity. Before Windows 95 was released I was using a 540MB Maxtor hard disk which was as large of a disk that MS-DOS could use. Larger 1GB and 2GB disks were slowly becoming available but the BIOS limitations forced the use of discrete PCI cards. Disk capacity limitations dogged the PC for decades to come.
The canard that search engines consider backlinks led to thousands of link sharing sites. Some automated the backlink and sought other places to post links. It did not take long before counterfeiters came out of the woodwork either.
Some spam messages were posted at such high rates on forums as to overwhelm database servers. The destructive nature of the spam bots suggests miscreants were intending on causing extensive damage. Early forums were not generally equipped with large amounts of storage.
QuickPar used to use a forum until a spambot flooded the database. At the time most web servers did not have much storage for the database. The forum software had no real security so the spambots overwhelmed it quickly.
More recently the Devnetwork forum seems to have been wrecked, posting has been broken for 18 months now. There is no obvious spam so I am speculating that the forum is broken and that the administrator cannot fix it.
Before WordPress et al surfaced, forums were very common. Now there are far fewer of them and many have been trashed by spammers. Fighting spammers has been a full time job. Once a spammer has a target the attack can be so destructive. Given the forum is destroyed, there is no gain for the spammers.
Back when the site was using phpBB, spam was a daily problem. Spammers even broke all the different CAPTCHA schemes. Puzzles ended up being the solution to block spambots. For example: what is the dot product of (3,9, 0) and (0, 1, 22).
While spam has finally slowed somewhat, there are new problems that are even worse. Miscreants now try to break into servers and copy the databases for criminal purposes. Credit card and payment processor had a lot of work cut out for them to prevent fraudulent card use.